NASA | GSFC | TESS | 2020 Jun 30
Measurements from NASA’s Transiting Exoplanet Survey Satellite (TESS) have enabled astronomers to greatly improve their understanding of the bizarre environment of KELT-9 b, one of the hottest planets known.Explore KELT-9 b, one of the hottest planets known. Observations from NASA's TransitingClick to play embedded YouTube video.
Exoplanet Survey Satellite (TESS) have revealed new details about the planet’s environment.
The planet follows a close, polar orbit around a squashed star with different surface
temperatures, factors that make peculiar seasons for KELT-9 b. Credit: NASA/GSFC/SVS
“The weirdness factor is high with KELT-9 b,” said John Ahlers, an astronomer at Universities Space Research Association in Columbia, Maryland, and NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “It’s a giant planet in a very close, nearly polar orbit around a rapidly rotating star, and these features complicate our ability to understand the star and its effects on the planet.” ...
Located about 670 light-years away in the constellation Cygnus, KELT-9 b was discovered in 2017 because the planet passed in front of its star for a part of each orbit, an event called a transit. Transits regularly dim the star’s light by a small but detectable amount. The transits of KELT-9 b were first observed by the KELT transit survey, a project that collected observations from two robotic telescopes located in Arizona and South Africa. ...
KELT-9 b is a gas giant world about 1.8 times bigger than Jupiter, with 2.9 times its mass. Tidal forces have locked its rotation so the same side always faces its star. The planet swings around its star in just 36 hours on an orbit that carries it almost directly above both of the star’s poles.
KELT-9 b receives 44,000 times more energy from its star than Earth does from the Sun. This makes the planet’s dayside temperature around 7,800 degrees Fahrenheit (4,300 C), hotter than the surfaces of some stars. This intense heating also causes the planet’s atmosphere to stream away into space. ...
KELT-9 b’s Asymmetric TESS Transit Caused by Rapid Stellar
Rotation and Spin-Orbit Misalignment ~ John P. Ahlers et al
- Astronomical Journal 160(1):4 (2020 July) DOI: 10.3847/1538-3881/ab8fa3
- arXiv.org > astro-ph > arXiv:2004.14812 > 28 Apr 2020
viewtopic.php?t=39423